New early antigen test available to male volunteers

The Barbados Cancer Society is looking for male volunteers to participate in a research initiative probing the effectiveness of a new method of testing for prostate cancer at the very early stages.

President of the Cancer Society Dorothy Cooke-Johnson told Barbados TODAY that the Prostate Circulating Antigen (PCA) antigen test, involving a small blood sample has been developed by Wren Laboratories, Yale University, USA. She said it enables the assessment of minute traces of fragmented DNA circulating in the blood, which may signal the presence of prostate cancer from a pre-invasive stage, that is, before it has started to grow significantly in the prostate gland itself.

The test is based on the collection of a blood sample, just as is done with the Prostate Specific Antigen (PSA) testing. From this small amount of blood, it is possible to detect a novel, and very specific circulating gene signature, composed of fragments of DNA which are associated with the presence of prostate cancer or “pre-cancer”. These are referred to as biomarkers and analysis of these markers can lead to earlier and more specific diagnosis, even when the tumour is minute. They can also indicate, through the DNA fragment characteristics, the degree of aggressiveness of the future tumour.

“The project has been initiated by Professor R David Rosin, First Vice President of the Barbados Cancer Society, and facilities have been set up at the society’s headquarters in Henry’s Lane to offer the test to men who sign up for the programme. The first clinics started last week and the Cancer Society is seeking to contact men to participate in this trial. Two hundred and fifty men can attend the first group, with a further 250 subsequently. Men must pay the processing fee of BDS$50 for the PSA test, which is taken simultaneously, but there is no charge for the new DNA biomarker test’, otherwise called the PCA test,” she said.

The president pointed out that Barbados is one of just a few countries keen to obtain and offer the test. She said although at present it is a costly test to produce and evaluate, it is currently being offered free to Barbadian men. Cooke-Johnson also noted that the test specimens must be stored at minus 80 degrees, and sent to Wren Labs at Yale University, USA for evaluation.

She said once the trial has been completed in the USA, the PCA transcripts will be returned exclusively to the trial coordinator in Barbados.

“This very sensitive test could indicate the biochemical presence of very early DNA-fragment indicators, even though there may not yet be signs or symptoms of the disease, and available imaging may not be able to confirm or locate any tumour tissue in the prostate.

“However, such a very early warning is an indicator that the propensity exists to develop a prostate neoplasm. This allows the man, his physician, and the Barbados Cancer Society, to be alert and proactive with the client’s results and ensure adequate follow-up with his PSA and annual medical consultations. Larger trials worldwide will confirm the early findings, leading to cheaper and broader distribution of the PCA test,” Cooke said. 
(anestahenry@barbadostoday.bb)